Concrete slab and supporting base



Dec. 4, 1962 G. s. PINTER 3,066,448

CONCRETE SLAB AND SUPPORTING BASE Filed Sept. 14, 1959 George S. Pinter INVENTOR.

AGENT.

United States Patent 3 066,448 CONCRETE SLAB AND SUPPGRTING EASE George S. Pinter, 33 East End Ave, New York 28, NY. Filed ept. 14, 1959, Ser. No. 839,675 3 (Ilaims. (CI. 50-80) My present invention relates to concrete structures of the type wherein a platform, a slab or some other elongated member rests in a generally horizontal position on spaced-apart supports rising from a suitable base.

In the construction of platforms or floors supported on girders, for example, difficulties have heretofore arisen in properly maintaining the constituent slabs thereof at a desired level by means of spacers or feet extending upwardly from the girders. These diiiiculties re sulted from the fact that the top flanges of the girders were never perfectly even and that, consequently, certain of the supporting spacers had to differ in length from the others in order to compensate for these irregularities. The use of shims to change the effective length of the spacers was, however, cumbersome and, moreover, tended to introduce an undesirable stress distribution liable to weaken the structure.

It is, therefore, an important object of my present invention to provide conveniently adjustable means for supporting a concrete member above a girder or other generally horizontal base in a manner avoiding the above difliculties.

It is another, related object of the invention to provide a process for erecting a concrete structure of the type set forth in a way which will reliably maintain such structure in a perfectly level position regardless of the uneven character of its base.

A feature of this invention resides in the provision of a spacer composed of complementary male and female elements rotatably engaging each other along a helical contact surface (which may be in the form of a ramp or a screw thread) so that relative rotation of these elements will change the efiective length of the spacer; with one of the elements firmly imbedded in the concrete member, the other is immobilized (as by welding) with respect to the supporting base after the necessary adjustment has been made. Advantageously, in accordance with a more specific feature of my invention, the concrete member is originally poured around the female element of each spacer which is downwardly open to receive the male element.

The above and other objects, features and advantages of the present invention will become more readily apparent from the following description, reference being made to the accompanying drawing in which:

FIG. 1 is a side-elevational view, partly in section, of a concrete structure embodying the invention;

FIG. 2 is a cross-sectional view taken along line II-II of FIG. 1;

FIG. 3 is a cross-sectional view taken along line llI-III of FIG. 1;

FIG. 4 is a view similar to FIG. 2, illustrating a modification;

FIG. 5 is another view similar to FIG. 2, showing a further embodiment of the invention; and

FIG. 6 is a perspective view of the spacer shown in FIG. 5.

In FIGS. 1, 2 and 3 I show a structure comprising a concrete slab 10 supported on two parallel girders 16 by spacers composed of female elements 12 and male elements 15. The male elements, shown here as sections of pipe having a threaded portion received in the female elements or nuts 12 which are imbedded in depending cross-ribs 11 of slab 10, are welded to the nuts at 13 and to the girders 16 at 17. Each nut 12, to which anchor rods 14 have been secured (e.g. by welding), is closed at the top by a cover plate 12a adapted to prevent concrete from entering its threaded portion during pouring. The slab it with its two ribs 11, forms part of a platform in which a series of such slabs are pos1t1oned alongside one another and are supported on the two girders 16 extending the full length of the platform. There are four sets of spacer elements 12, 15 to a slab, each set being located at a cross point between one of the ribs 11 and one of the girders 16.

To assemble the slab 11 with the girders 16, the pipes 15 are threaded into the nuts 12 previously imbedded in cross-ribs 11; the slab is then positioned over its twogirder base and the pipes 15 are individually turned further into or out of nuts 12 to support the slab 10 horizontally at four points, whereupon the pipes are welded at 13 to the nuts 12 and at 17 to the girders 16 so as rigidly to secure the slab to the base. The pitch diameters of the female and male threads are respectively oversize and undersize to produce a relatively loose fit, thereby allowing for a limited tilting of the pipes 15 with respect to the slab 19 to compensate minor deviations of the girder flanges from the horizontal and/or to enable a positioning of the slabs at a slight inclination to form a ramp.

FIG. 4 illustrates a modification of the concrete structure of FIGS. 1, 2 and 3 further comprising a locking nut 13, engaging the lengthened thread of pipe 15, for more rigidly securing the spacer element 15 to the nut 12 before the assembly is consolidated by welding. In this case the pipe 15 is advantageously welded to the nut 13 rather than to the nut 12.

FIGS. 5 and 6 show an embodiment of my invention in which a bushing 22 provided with anchor rods 24 is imbedded in a concrete slab 20, as described with reference to nuts 12- and slab 10, and is adapted to receive a male spacer element such as a pipe 25 having an extremity provided with a helical ramp 29', equivalent to a one-turn screw thread, adapted to contact a complementary helical ramp 29" within the bushing 22. It will be readily apparent that the slab 20 may be elevated or lowered, through a maximum distance substantially equal to the sum of the pitches of the two helices, by a rotation of the pipe 25. The latter may then be welded to the bushing 22 and to the supporting girder to secure the slab.

It will thus be seen that I have provided a unitary supporting member 12, 15 or 22, 25, for the purpose described, wlnch will withstand both vertical and horizontal forces as well as bending moments and shocks.

Although the invention has been described with reference to specific embodiments, it will be apparent that various modifications, readily understood by persons skilled in the art, are to be included within its spirit and scope except as further limited in the appended claims.

I claim:

1. A structure comprising a base including a plurality of horizontally spaced metallic girders, a concrete slab above said base, and spacing means supporting said slab with clearance above said girders with initial freedom of relative horizontal shifting on said girders; said spacing means consisting of a plurality of horizontally spaced metallic nuts respectively overlying different ones of said girders, said nuts being fixedly imbedded in said slab with exposed lower surfaces and being open toward the underside of said slab, and a like plurality of substantially vertical metallic columns with screw-threaded tops rising from said girders in threaded engagement with respective ones of said nuts and adjusted therein for a leveling of said slab above said girders, said columns being welded to said nuts at said exposed surfaces thereof so as to 3 constitute unitary supporting members adapted to withstand both vertical and horizontal forces as well as bending moments and shocks, said columns being also welded to said girders whereby said slab, said base and said columns are joined 'into a rigid unit.

2. Astructure according to claim l wherein said slab is provided with a plurality of depending cross-ribs extending transversely to said girders, each of said nuts being located at a cross point between one of said ribs and one of said girders.

3. A structure comprising a metallic 'base, a concrete slab above said base, and spacing means supporting said slab above said base in a generally horizontal position, said spacing means comprising a plurality of nuts, irnbedded in said slab and open toward the underside thereof, and alike plurality of screw-threaded bolts rising from said base and threadedly engaging respective ones of said nuts with'a fit loose enough to have initially permitted a limited angular adjustment between each bolt and the respective nut so as to enable a shift of said slab relative to said base, said bolts being welded to said base and to said nuts whereby said slab is immobilized relatively to said base.

References Cited in the file of this patent UNITED STATES PATENTS 614,530 Brown Nov. 22, 1898 1,761,321 Wells June 3, 1930 1,948,093 Baird et a1 Feb. 20, 1934 1,949,045 Ferguson Feb. 27, 1934 2,309,451 Hasenburger et a1 Ian. 26, 1943 2,466,106 Hoge Apr. 5, 1949 2,765,135 Chellis Oct. 2, 1956 2,812,834 Le Jeune Nov. 12, 1957 2,881,876 Williams Apr. 14, 1959 FOREIGN PATENTS 251,3 08 Great Britain Apr. 26, 1926 113,886 Austria July 25, 1929 466,044 Great Britain May 21, 1937 678,972 Great Britain Sept. 10, 1952 1,008,897 Germany May 23, 1957 

